Conventional wireless telephones generally offer both voice and data communications capabilities and allow real-time voice communications. As described below, such real-time communications are not always desirable by a user who wishes only to receive a message without having his current activity disturbed.
Pagers, on the other hand, are miniature receivers which receive data transmissions from at least one paging terminal which covers a selected geographic area. A pager is generally tuned to a particular tone or data bit-modulated frequency that is shared with many other pagers. A particular sequence of tones or data bits is used as an address or the identification of a selected pager. Reception of the particular sequence activates an acoustic, tactile or visible alert, thereby indicating that a call has been placed to the paging terminal from a telephone connected to the public switched telephone network (PSTN) or other telecommunications network and communicated via the transmitter to the pager. Depending on the complexity of the pager, the paging device may receive a voice or data message following the alert, or the alert alone may simply indicate to the user that a call was made and a prearranged action should be taken. To respond to a page, the paged party typically must find an available conventional or wireless telephone and initiate a telephone call to the party that initiated the page.
There have been several attempts to make wireless telephones a substitute for pagers by incorporating pager features into the wireless telephone system. The objective of these attempts is to enable the wireless telephone user to receive short digital messages and to allow the user to screen incoming calls and respond to selected messages when time allows, without interrupting the user's activities.
One such attempt is called short messaging services (SMS). Using SMS, an alpha-numeric or numeric message (hereinafter collectively "alpha-numeric message") is transmitted to a wireless telephone and appears on the screen of the unit. This may be accomplished in at least three different ways: First, the caller may call the wireless telephone number and be transferred to the user's voice mailbox. The caller is then prompted to enter the caller's telephone number or other alpha-numeric message, which is transmitted to the wireless telephone by the voice mail system. Second, a caller can use either e-mail or a web page to send an alpha-numeric message to a user's wireless telephone. A third way is to use a paging system such as a voice response system (VRS), whereby the caller calls a toll-free number, is prompted by the system to enter the user's PIN number (usually the user's 10-digit telephone number or a 7-digit alias) and the caller's telephone number or other alpha-numeric message which is transmitted to the wireless telephone by the VRS. Only the first of these methods permits the caller to call the user's wireless telephone number, as opposed to calling another number or accessing e-mail or the world-wide web. Moreover, these SMS methods have the drawback that their use is not controlled by the wireless telephone user, and consequently he cannot force callers to use SMS during time periods when he does not want his activities disturbed by calls to his wireless telephone.
From the wireless telephone user's perspective, he has several options for making his wireless telephone function like a pager. Conventional wireless telephones have several operating modes, including silent or meeting mode and a pager mode. In silent mode, there is no audible or tactile ringing signal in response to incoming calls. In meeting mode, the user is alerted by different ringing signals (e.g. different tone volumes or patterns) corresponding to various Caller IDs stored by the user in the memory of the wireless telephone. In pager mode, the user is alerted to an incoming call with yet another distinguishable tone. In any of these conventional modes, unless the user answers the call, the caller must wait several rings before being transferred to voice mail, where he is prompted to leave either an alpha-numeric or recorded voice message for the user. Although the ringing signal is typically silenced in both the silent mode and pager mode, the caller still must wait a system-determined time interval (e.g., 60 seconds) before being transferred to voice mail. In addition, in some wireless telephone systems such as the Global System Mobile (GSM) system (implemented in Europe, Australia, New Zealand and parts of the Orient), a user can screen calls based on the Caller ID and send selected calls directly to voice mail by pushing a button. Even in the GSM system, however, unless the user accepts or rejects a call, the caller must wait several rings before being transferred to voice mail.
In view of the foregoing drawbacks in existing wireless telephone systems, an object of the present invention is to provide a wireless telephone which functions similar to a pager. Another object of the invention is to provide a pager mode for a wireless telephone in which incoming calls are transferred immediately to voice mail without waiting for 60 seconds or other system- or user-determined time interval for allowing wireless telephone users to accept incoming calls. A further object of the invention is to provide a high priority screening feature which allows certain preselected high priority calls to circumvent the pager mode and be answered by the wireless telephone user in the normal fashion. A still further object of the invention is to provide a screening feature which permits the user to screen the Caller IDs of all incoming calls before they are transferred to voice mail, while the wireless telephone is in pager mode.